My wife loves using the laptop on trips we take, and we like being able to watch movies... so we normally use a power inverter in the car on long trips.

I'm looking right now at basically buying an off the shelf inverter and mounting it somewhere under the dash with only a 110v outlet showing somewhere easily accessible to the passenger seat.

I've started looking at off the shelves, and right now i'm looking at two candidates, a 80w/150w peak tiny (10a max), or a 150w/300w peak (20a max). The small one would be cake to fit under the dash (we're talking about a 2" cube-ish, while the 150w has more substantial mass (maybe 4x6x1.5"-ish) to hide.

The 10A version could easily be tied into the cig. lighter wiring (15A fuse), but the 20A version would need its own supply.

Any suggestions? I'd like the higher version, and fusing it isn't a problem because the units each have their own fuse... which I would rewire to be fused in at the main fusebox for the 20A, or would eliminate for the 10A since there's already a fuse on the cig lighter if I tie that one in there. If I do the 20A, does anyone know if there's extra power already at the fuse box available? (Assume I already have the fog lights installed )